LAUSR

Abstract Considering the global production of banana, a large amount of banana peel (BP) waste is being generated world widely. Thus, pyrolysis of BP was investigated to develop a technically reliable platform for the simultaneous waste management and energy recovery. To synergistically increase the sustainability of BP pyrolysis, this study adopted carbon dioxide (CO2) as a raw material and examined the production of syngas as a function of temperature in reference to the N2 environment. CO2-cofeed pyrolysis expedited the thermal cracking of volatile pyrolysates from BP, resulting in the gas phase homogeneous reaction between CO2 and the pyrolysates at ≥420 °C. This promoted CO formation in the temperature region, and more than 20 times of CO formation was shown in comparison with pyrolysis in the N2 environment. These genuine mechanistic roles of CO2 offer a new mean for converting CO2 into CO. Also, CO2-cofeed pyrolysis of BP increased the aromaticity of biocrude (pyrolytic oil), expediting dehydrogenation of liquid pyrolysates without using any catalysts. Moreover, modification of biochar surface morphology under the CO2 condition was observed. Conclusively, this study informed a key clue for maximizing the carbon exploitation in the carbonaceous waste, which directly leads to the environmental benefits due to the use of CO2 as a reactant. CO2-cofeed pyrolysis can be an innovative and strategic thermo-chemical process to valorize food wastes.